Adjustable pitch propeller



Feb 3, 1948. e. w. HARDY 2,435,540

ADJUSTABLE PITCH PROPELLER Filed Nov. 15, 1945 a Sheets- Sheet 1 ATTO/F/VEV' Feb. 3, 1948. G. w. HARDY ADJUSTABLE PITCH PROPELLER FiledNov. 15, 1945 3 Sheets-Sheet 2 a aw M CT A J E W;

Filed Nov. 15, 1945' s Sheets-Sheet 3 .Y 7.? E0/% fi m? mr mH WW m M F ATT GENE Y 3 while permitting the shank to be rotated about its axis.

The retainer l3 preferably is made in congruent halves and its outersurface is finished to fit accurately into the cylindrical bore 1 whenthe halves are fitted onto the shank 8 of the blade. The ring 13, wheninstalled, forms in operative effect a part of the shank 8, beingrotatable therewith and fixed in position axially thereof.

In order to anchor the blades 3 in the ends of the connector 5, eachretainer I3 is of larger external diameter than the associated shank 8so as to provide an annular locking shoulder [4 the connector 5. Anexternally threadedcastellated collar :5 slidably and rotatably embracesthe shank 8 outwardly from the retainer l3 and engages the complementarythreaded portions 6 of the connector 5. By engagement of the inner endof the collar 5 with the shoulder I4 of the retainer It, the blade 3 isanchored against movement outwardly axially of the connector 5 but canbe rotated about said axis. For locking the blade against rotation aboutthe longitudinal axis of the connector 5, the outer ends of theconnector 5 are castellated, as indicated at it, and a suitable key I!is interfitted with aligned notches of the castellations l6 and those ofthe castellated collar IS. The key I! is held in position by means of anexternal clamping-ring i8 secured by a bolt l9. Due to the castellationsof the retaining collar l5, the outer end of the castellated portion canspring and act as gripping jaws when drawn tightly against the propellerblade by the clamping ring l8, thus effectively clamping the propellerblades in properly adjusted pitch position.

In order to provide for locking the blades in a large number ofrelatively rotated positions about their longitudinal axes, so as topermit very fine adjustments for balance, the notches of thecastellations l6 of the connector 5 are angularly disposed about thelongitudinal axis of the connector 5 at different angles than are thoseof the collar It: thus providing a Vernier effect in aligning any notchof the collar IS with a notch of the connector 5. For example, an evennum ber of notches may be provided in each end of the connector 5 and anodd number in the associated collar l5. In the form illustrated, ninenotches are provided in each end of the connector 5 and four in eachcollar.

With this arrangement, the adjustment of a blade axially of theconnector 5 for balance is independent of the adjustment'of the otherblade and the adjustment of a blade rotatively of the axis of theconnector 5 for pitch is independent of the rotative adjustment of theother blade. Also, the axial and rotative adjustments of a single bladeare independent of each other.

Adjacent its inner end, each shank 8 has an external annular pilot area20.

Mounted within the connector 5 is a rigid spacer 2! which is preferablya single tube as illustrated in Figs. 2 and 3. The tube may be splitlongitudinally in case the impeller shaft 2 is of the tapered, keyedtype, as illustrated in Figs. 6

and 7. The spacer 2| is ground or otherwise finaccurately finished toprovide annular seating areas 22 for operative engagement withcomplementary seating areas 23 of the shanks 8. In the illustrativeexample herein, instead of forming the complementary seating areasdirectly on the shanks, the seating areas of the shanks are formed onthe inner ends of the retainers l3 which are fixed axially of therespective shanks and form parts thereof;

The spacer 2| is finished to a very accurate length so that when theseating areas 23 of the shanks 8 are in engagement with the seatingareas 22 of the spacer, the blade shanks, and therefore the bladesthemselves, are accurately .positioned the proper distance from eachother -l6.i

axially of the connector 5.

As mentioned, the spacer 28 is slidable axially in the bore '1 of theconnector 5 and is accurately guidedtherein. The spacer 2i is providedwith a plurality of transverse openings 24 and large aligned diametralopenings 25, for purposes later 1 to be described.

\ accurately with the ends of the retaining body 4. The rear plate 2'!is peripherally integrally connected to the retaining body 4 by weldingat 2'! so as to form substantially a unitary structure therewith. Therear plate 21 preferably is of sufficient thickness so that when fittedinto the end of the retaining body 4, its inner face lies close to butspaced from the nearest portion of the circumferential surface of theconnector 5-at diametrically opposite sides of the shaft .2. Along theseareas of near contact and for a material distance each side thereof,circumferentially of the connector, the plate 27 is permanentlyintegrally joined to the connector 5, by Welding, as indicated at 28.The space resulting from the spacing of the plate 21 and connector 5 andthat resulting from the curvature of the connector 5 away from theplanar inner face of the plate 27 are filled in with the welding metalfor a material distance each side of the region of near contact. Theplate 28 may be similarly welded or integrally connected to the retainerbody 4 if desired, but generally is left unwelded so that it may beremoved easily.

Likewise, as illustrated'in small part at 29, the retaining body 4 ispermanently integrally connected to the connector 5 where the connector5 intersects the circumferential wall of the retainer 4, preferably bywelding.

Aligned openings 39 are formed in the plates 26 and 21 for receivingsuitable tie-bolts Stand cooperating clamping nuts 32. The nuts 32 arecylindrical so as to fit accurately in the openings 30 of the plate 21and openings 33 of the connector and each has a flange head with flatsfor engagement by a wrench. Part of the bolts 3| extend through theconnector 5 and part are spaced therefrom. I

Because of a number of the bolts passing through the connector 5suitable openings 33 are provided therein, these openings and theopenings 24, heretofore described, of the spacer 2| are alignable witheach other, the openings 24 of the spacer being made larger than thebolts which extend therethrough so as to permit adjustment of the spacer2| axially of the connectori after the bolts are inserted. The diametralopenings has suitable opeffirigsfias iillustifatedffof accqmmod'atmg'snugl the nets *aztr' t e cramp ng fbol'ts'f'3l. Injofder to'pieventdist'ortionfof rate thee'onr'i etor secured to the outefiiefibhtmlweilofthe'tiibufi 'laff'etaining body I w 7 It'isapparentIrorn"theifoifegoing"'des'e iption thatwhen'the blides a einitiatl ly iristauewm the'e'nds of the'onheoto with thfspcr 2| oeeijnglw throegnwmemne haft 2 mayiiess.

' tdjiistment is oirimjetedf mejmaaes'may be set eecurateiy; one" attime: "ilffth ia 'operfi'otated bitch bo sition eboiitthe "p theirshelnk With- ;out'dis'tiifhin'g'the Bimini: by slightly loos hing theeasteilatedbollef'bf on 'bli'cie'at a time while oper p1 hddjtistii'ient the eqpn'ectm; without vchanging the pitch. When thefaekiai able endwise of the connector 55.

, at Ill, and the adjacent inner ends of the por- 'As a result of theseating of the portions in the connector, as at 10, and the seating oftheir ends, as at H, they act, in so far as spacing is concerned, as asingle unitary spacer, adjust- The spacer 64 may be made and machined inone piece, then cut into end portions and its inner ends finished toproper complementary seats. For purposes of the claims, the spacer 64 isconsidered as a unitary spacer the same as the spacer 2|, except wherespecifically recited otherwise in the claims.

I claim:

l. A propeller hub comprising a tubular connector having its ends openand adapted to receive axially, and to accommodate slidably endwise ofthe connector, shanks of propeller blades, a tubular spacer within andcoaxial with the connector and slidable endwise thereof to differentadjusted positions, said spacer having seating areas facing toward theends of the connector and adapted for seating engagement, when theshanks are received in the connector with complementary seating areas ofthe shanks, means on the connector adapted for connection tocomplementary means of the blade shanks for connecting the blade shanksin adjusted positions axially of the connector while the seating areasof the shanks and spacer are in seating relation to each other, andmeans for connecting the connector to a propeller shaft with theconnector axis intersecting the shaft axis at a right angle.

2. A propeller hub comprising a tubular connector having its ends openand adapted to receive axially, and to accommodate slidably endwise ofthe connector, shanks of propeller blades, a tubular spacer fittingwithin and coaxial with the connector and slidable endwise thereof todifferent adjusted positions, said spacer having seating areas facingtoward the ends of the connector and adapted for seating engagementconcurrently with complementary seating areas of the shanks when theshanlm are received in the connector, said spacer also having pilotsurfaces extending generally lengthwise of the spacer for engagementwith complementary pilot surfaces of the shanks for guiding the shanksinto coaxial relation with the spacer and connector,

means for connecting the shanks in fixed position in the connector, andmeans for connecting the hub to a propeller shaft.

3. A propeller hub comprising a tubular retaining body, a tubularconnector extending diametrically therethrough and having its ends opento receive axially, and to accommodate for sliding movement endwise ofthe connector, shanks of propeller blades, a spacer fitting within andin coaxial relation to the connector and slidable endwise thereof, saidspacer having seating areas facing generally toward the ends-of theconnector and adapted for engagement with complementary seating areas ofthe propeller blade shanks when the shanks are inserted in theconnector, connecting means for connecting the blades to the connectorin adjusted position of the blades axially of the connector and inadjusted pitch position, and means rigidly connected to the connectorand to the retaining body and adapted for connection to a propellershaft.

. 4. A propeller hub comprising a tubular retaining body, a tubularconnector extending diametri- V cally through the retaining body andhaving its ends open, each end of said connector being adapted toreceive axially and snugly accommodate a propeller blade shank, meanscarried by the connector for securing the associated blade shank inadjusted pitch position and adjusted position axially of the connector,end plates in and coaxial with the retaining body at opposite sides ofthe connector, at least one of said plates being permanently rigidlyconnected with the connector along a portion of its inwardly disposedface and permanently rigidly connected to the retaining body aboutitsperiphery, said plates having aligned sets of openings parallel to andoffset from the axis of the retaining body, and bolts extending throughsaid sets of aligned openings respectively for connecting the plates andconnector to a propeller shaft;

5. A propeller hub comprising a tubular retaining body, a tubularconnector extending diametrically through the retaining body, a tubularspacer within, coaxial with, and slidable endwise of, the connector,each end of said connector being adapted to receive axially and toaccommodate snugly a propeller blade shank, the tubular spacer havingseating areas facing generally toward the ends of the connector andadapted to abut complementary seating areas of the shanks, means carriedby connector and operatively connectable to the blade shanks forsecuring the blade shanks independently in adjusted'vpositions axiallyof the connector, end plates in and coaxial with the retaining body atopposite sides of the connector, at least one of said plates beingpermanently rigidly connected to the connector along a portion of itsinwardly disposed face and permanently rigidly connected to theretaining body about its periphery, said plates having sets of alignedopenings parallel to and offset from the axis of the retaining body, theconnector having openings aligned with some of the plate openings, boltsextending through said sets of aligned openings respectively forsecuring the hub to a propeller shaft, and said tubular spacer havingenlarged diametral openings for affording passage of some of said boltsthrough the spacer in different adjusted positions of said spacerendwise of the connector.

6. A propeller hub comprising a tubular retaining body, a tubularconnector extending diametrically through the retaining body, a tubularspacer within, coaxial With, and slidable endwise of, the connector,each end of said connector being adapted to receive axially and toaccommodate snugly a propeller blade shank, the tubular spacer havingseating areas facing generally toward the endsof the connector andadaptedto abut complementary seating areasof the shanks,

rneans carried by connector and operatively con- ',nectable to the bladeshanks for securing the blade shanks independently in adjusted positionsaxially of the connector, end plates in and coaxial with the retainingbody at opposite sides of the connector, at least one of said platesbeing permanently connected at itsinner face to the connector andpermanently connected at its periphcry to the retaining body, saidplates having sets of aligned openings parallel to and oifset from theaxis ofthe retaining body, the connector having openings aligned withsome of the plate openings, bolts extending through said sets ofopenings respectively for securing the hub to a propeller shaft, saidtubular spacer having enlarged di me r i cpsnmssl jcr ficr-ding passa ect cmc of said bolts through the spacer in diiierent, ad-L justedpositions of said spacer ,endwiseof the connector, andsnacer sleeyesonpa t or the bolts f r rein-forcing he nlates againstrd sto tioninwardly, H

7. A propeller hub;comprising a tubularretain-rl ins odsn. c axial ubu cnec or e s. c e. tending radially, outwardly from, the retaining bodyand having theirendsopemeachofsaidconnector meansbeing' adapted,toreceive axially and. n ly c ommodate. a pr p l r. la e hank, meanscarried, by connector, means for securing, the associatedbladeeshankI-in; adjustedposition axially of the connector, means, end,platesin and coaxial with the retainingbody atopposite sides of. theconnector. means, at least oneptsaidplates being connected with the.connectoli-mfiahsat its. inwardly disposed face nd, beingconnected, tothe retaining body at its .periphery-,,said,plates haying, aligned setsof. openings... parallel-to and. offset fromthe axis of the retaining,body,-bQ1li .-.Q ten,d ing through said sets of openingsrespectivelyforconnecting the. plates and connector .to' a D D: pe ler shaft, a d s dconn tor means being di rectly connectedto the retaining body,-

8..A..prope11er huhcomprisinga tubular, retain; s d c xia tub la cnector meanscx: tend adi y u ardly r m. he-r tainin body, eachconnector. means being openiat, itsends to, receiveaxiallyshanksotpropellenblades. and toaccommodate.said shanksforslidingmoyement a al of e c n c orv mea s a i ids ac r. Within n n. xialr l t on t he-,- cnn ct n means. and guided therein. at, its ends .forsliding s -th r ,s id s ac rha in sea i r as facing generally towardtheouteigeiids lithe; con e t a s 1 dapted iqne asc cnt wit complementaryseating areas ofthev propeller blade shanks-.-when--,the.;. shanks areinserted in the connector means, connecting means for connecting theblades to the connector means in ad- J'1 t s o o he ladcsaa ally i. -.th..c nnector means, and means connecteito the con nector means and to theretaining body and adapted forconnection to a propeller.v shaft.

9. A propeller hub comprising a tubular Lemma n i b dy, connectormeansh. i oaxia1: tubular end portions extending radially outwardlythrough the retaining body and adapted to receive axially, and toaccommodate slidable endwise of the connector means, shanks of propellerblades, a rigid spacer within and coaxial with the end portions of theconnector means and slidable endwise to different adjusted positions,said spacer having seating areas facing toward the outer ends of theconnector means and adapted for engagement, when the shanks are receivedin the connector, concurrently with complementary seating areas of theshanks, and means on the connector adapted for connection tocomplementary means of the blade shanks for connecting the blade shanksin adjusted positions while the seating areas of the shanks and spacerare in seating relation to each other, said connector means beingrigidly connected to the circumferential wall of the retaining body, aplate coaxial with the body and peripherally connected thereto at oneend of the body and having its inwardly disposed face connected to theconnector means, and means for connecting the hub to a propeller shaftwith the said bladesfitting ,intof said open ends, and supported therebyin coaxial relation, and for sliding movementindepen-dently axially of.the connector, a rigid. spacerfitting within and movable axially of theconnector and having seating areas facing toward the ends, of theconnector, means 011 the shanks with seating. areas infixed relationaxially of the shanks and complementary to those of the spacer,connecting means for interconnecting the shanks. and connector inaxiallyadjusted positions, and means for connecting the hub to a shaft.

, 11. A propellencomprisinga tubular connector having, itsiends,open,;.propeller blades, shanks on. saidblades fitting, into said. openends and supported thereby. in: coaxial relation and, for, slidingmovement. independently axially of the, connector, a spacer fittingwithin. and movable, axially of the. connector. and having. seatingareas-facing toward. theends of the. connector, means on, thetshankswith, seating areas in. fixed. relation axially of, the-, -shanks and. cm'plemen-a tary tothose oi the spacer, connectingmeans for.interconnecting, theshanks. and, connector in axially adjustedpositions, said connectingmeans, including castellated collars,embracingv the. shanks respectively and slidable axially thereofandhaving a eoaxial ..threaded. portion, said connector having avcomplcmentary. threaded portion cooperable therewith,;the ends of saidconnector being castellated, means. cooperating with the. castellationto lockthe collar againstrotation and means for connecting the-propellerto a,

shaft, V

12. Apropeller comprising a tubular connector hailing its. ends, open,propeller blades, shanks.

axis of the connector means intersecting the shaft I on, saidbladesfitting ,into said open .ends and, supported. thereby-in,coaXialrelation and for sliding movement independently, axially. of theconnector, segmentalretaining collars surrounding a portion of the,shanks, respectively, within, the, connector. and,,intetfltting,;with.the shank for anchoring theretaining; collar, and, shank, againstrelatiyeaxialmovement, said. collars haymg radial. shoulders of...greater diameter than the. shanks andfacingtoward, the outer ends of,the connector, me,ans.,-ad.ustableaxially ofand connected to v the,connectors and engaging. the; shoulders for restraining the shanks frommovement axially outwardly from their axially adjusted positions in theconnector, and means for connecting the propeller to a shaft.

13. A propeller comprising a tubular retaining body, propeller blades,shanks on the blades, a tubular connector extending diametricallythrough the retaining body, and adapted to receive the shanks in itsends for supporting the blades, cover plates fitting into the ends ofthe retaining body and rigidly permanently connected to the retainingbody about their periphery, atleast one of said plates being adapted forconnection with a propeller shaft in coaxial relation to the retainer,means connecting the plates to the connector for rotation therewithabout the axis of the plates.

14. A propeller comprising a tubular retaining body, propeller blades,shanks thereon, a tubular connector connected to and extendingdiametrically through the retaining body and adapted to receive theshanks axially, cover plates fitting into the ends of the retaining bodyand rigidly permanently connected to the retaining body about theirperiphery, means connecting the plates to the connector for rotationtherewith about the axis of the plates, means for connecting the platestogether and to a propeller shaft including bolts spaced about andparallel to the axis of said plates, each bolt being secured to bothplates and spanning the distance therebetween, reinforcing sleeves onsome of the bolts and engaging the plates at each of their ends, andmeans anchoring the other of the bolts directly to the connector.

15. A propeller comprising a tubular retaining body, propeller blades,shanks thereon, a tubular connector extending radially through the body,said shanks fitting in the ends of the connector, respectively, andbeing movable axially thereof, a spacer fitting within the connector andmovable axially thereof and having seating surfaces for spacing theblades axially, said blade shanks having complementary seating surfacesaxially rigid therewith and engaging the seating surfaces of the spacer,means for securing the shanks independently in axially adjusted positionin the connector with their seating surfaces in engagement with thespacer, cover plates each rigidly connected to the retaining body and tothe connector, bolts extending through said plates, and said spacerhaving openings affording passage of the bolts therethrough in theaxially adjusted positions of the spacer.

16. A propeller comprising a tubular retaining body, propeller blades,shanks thereon, a tubular connector extending radially through the body,said shanks fitting in the ends of the connector, respectively, andbeing movable axially thereof, a spacer fitting within the connector andmovable axially thereof and having seating surfaces for spacing theblades axially, said blade shanks having complementary seating surfacesaxially rigid therewith and engaging the seating surfaces of the spacer,said spacer havinginternal peripheral pilot surfaces at its ends, saidblade shanks having an external peripheral pilot surface complementarythereto, means for securing the shanks independently in axially adjustedposition in the connector with their seating and pilot surfaces inengagement with the spacer, cover plates each rigidly connected to theretaining body and to the connector, bolts extending through saidplates, and said spacer having openings afiording. passage of the bolts12 therethrough in the axially adjusted positions of the spacer.

17. A propeller comprising a pair of propeller blades, shanks on theblades, a tubular connector, said shanks fitting in the ends of the connector, respectively, and being movable axially thereof, and rotatabletherein about their axes, means for securing the blades in axially androtatably adjusted positions independently in the connector, a rigidspacer fitting Within the connector and movable axially thereof andhaving seating surfaces for spacing the shanks axially, said shankshaving complementary seating surfaces axially rigid therewith andengaging the seating surfaces of the spacer, and means for connectingthe connector to a propeller shaft.

18. A propeller comprising a connector having portions which are open attheir ends for receiving propeller blade shanks, propeller blades,shanks on the blades receivable in said portions and supported thereby,connecting means for each shank for interconnecting the associated shankand portion of the connector, each of said connecting means including acastellated collar embracing the shank and slidable axially thereof andhaving a threaded portion coaxial with the shank, said connectorportions having complementary threaded portions cooperable with those ofthe shank, the outer ends of said connector portions being castellatedwith the notches of the castellations open outwardly of the propeller, akey insertable into aligned notches of the castellations of the collarand connector portion, and with a portion lying along the shank, aclamping ring embracing the eastellated portion of the collar and thekey for clamping the castellated portion of the collar tightly againstthe shank and retaining the key in position in said aligned notches.

GORDON W. HARDY.

REFERENCES CITED UNITED STATES PATENTS Name Date Berliner Feb. 7, 1939Number

